Comments on: Emissions and the Tar Sands

By: The Keystone XL Pipeline | Serendipity

The Keystone XL Pipeline | Serendipity — Tue, 27 Sep 2011 03:25:47 +0000

[...] Others have eloquently explained the issue. I would recommend ClimateSight for a recent overview & background on the protests, and David Pritchard for a sober analysis of the emissions impact. [...]

By: John

John — Mon, 05 Jul 2010 14:37:29 +0000

What a lot of people don’t realize is that the process of gasification into syngas followed by Fischer Tropsche synthesis into marketable synthetic crude works on anything that burns, not just tar sands. If you fed the gasifiers trash and dried sewage and sequestered the charcoal byproduct as biochar then the process would be carbon negative.

By: David Pritchard

David Pritchard — Mon, 08 Jun 2009 00:16:12 +0000

Largely agreed, Bruce. Cost and efficiency are significant barriers. After all, the whole point of oil as a fuel is that it is 1) portable/energy-dense and 2) cheap. If you decide to use a point-source plant to convert it into an entirely different form (syngas / hydrogen) or distribute it (electricity), then you’re no longer taking advantage of its portability. And the tar sands+CCS+gasification+2nd CCS system you’ve described can’t possibly be a cheap process, compared to other electricity-generation techniques…

My money’s still on efficiency, plug-in hybrid electric vehicles, transit/walk/bike, and possibly all-electric-vehicles as the sensible ways forward.

By: Bruce

Bruce — Sun, 07 Jun 2009 11:21:18 +0000

Taking this analysis in isolation, it sounds like the problem is the burning of oil at locations far away from convenient CCS.

One natural conclusion is to gasify tar sands on-site into energy-containing molecules with more energy per carbon atom: syngas and hydrogen. If this gasification and reforming were done on site, carbon capture could be performed on both the CO2 emitted by the tar sand refining process, and the CO2 emitted in the hydrogen reforming process. The mobile emissions sources would have zero emissions (hydrogen) or high energy per carbon atom (natural gas).

Alternatively, stick your power plant on top of the tar sands refinery, and capture the CO2 coming out of the power plant as well. Export electricity to battery powered vehicles.

I’m not convinced the electrified / hydrogenized path will actually happen though … there are other barriers to that future.

By: David Pritchard

David Pritchard — Thu, 14 May 2009 01:37:54 +0000

Um… no. Yes, we will absolutely hit the peak of conventional oil and find that the tar / oil sands look attractive.

But the point of my post here is that even if you could eliminate the carbon during the extraction of the oil, the carbon from the burning of the oil will cause vast damage. The cumulative effect of using both the remaining conventional oil plus a substantial fraction of the remaining unconventional oil (like the tar sands) adds up to too much carbon—we likely need to cut off use of all oil before we get that far.

By: T1 Rex

T1 Rex — Mon, 13 Apr 2009 00:23:22 +0000

At some point we’re going to find that we still need petroleum but have gotten past peak oil without enough green infrastructure to take over completely. Then those tar sans will look pretty attractive. What might make extraction a better choice is to site power plants nearby and use the waste heat from nat gas or nuclear to provide the energy to get the oil from the sands.